Rod reducer

ABSTRACT

An instrument is provided for use in orthopedic surgery, such as for reduction of spinal rods. In one embodiment, a shaft is pivotably connected to a plate with an aperture, and a sleeve is slidable over the shaft and plate. A base member can be provided for ease in handling the instrument, which may include a ratchet mechanism connected to the sleeve. The plate is moved so that its aperture is oriented to allow an orthopedic implant, such as a Schanz-type screw, to be inserted into the aperture. After insertion, the shaft is moved so as to pivot the plate so that the plate grips or holds the implant. The sleeve is then slid over the shaft, plate and implant in contact with an elongated member, such as a spinal rod, or other implanted device or tissue. Further sliding the sleeve forces the elongated member toward or past the implant.

FIELD OF THE INVENTION

The present invention concerns tools for use in implanting orthopedicimplants during surgery. Specifically, the present invention discloses atool for reduction of a spinal support rod or other elongated orthopedicimplant member.

BACKGROUND OF THE INVENTION

In orthopedic surgical procedures, it is known to implant devices tosupport bony or other tissue, to correct deformities, to hold tissues inposition for healing after injuries or other surgery, and for otherpurposes relating to orthopedic health. For example, where correction ofa scoliotic or other abnormal curvature of the spine is desired, asturdy rod, plate, or other elongated implant member can be placed alongone or more vertebral segments to support or hold the segments in acorrected position. Bone screws, bone hooks or other fixation implantsare attached to vertebrae and connected to the elongated implant memberto provide the support.

Commonly, the fixation implants and the elongated implant member(s) areplaced separately, that is, they are not connected together prior toimplantation in the body. For example, bone screws may be implanted intovertebrae first, connectors may be placed on or around the screws (ifnecessary), and then the rod may be placed into the body. The rod orother elongated implant may be contoured prior to insertion toapproximate the curvature desired, or it may be contoured afterplacement adjacent the spine. In cases where a rod and bone screws orother fixation elements are separately placed, frequently the rod andscrews must be forced toward each other for connection. The process ofmoving a rod or other elongated member and fixation elements toward eachother for connection is generally termed “reduction” of the rod.

Reduction of a rod can be accomplished by hand, although the fluidenvironment of a surgical site can make reduction by hand quitedifficult. Several devices have been developed to accomplish rodreduction. Among them is the device disclosed in U.S. Pat. No. 6,146,386to Blackman et al., which is owned by the assignee of the presentdisclosure. That device places a cable around a fixation member andabuts a rod, so that retraction of the cable draws the fixation memberand rod toward each other. Other devices have used forceps-likestructures, threaded mechanisms, or other mechanical constructs to pushimplants together.

Most rod reducing devices are capable of use with only one or a few ofthe available implant systems. Accordingly, prior devices haveconnections that are only useful for connecting to certain fixationmembers or elongated members. Thus, their connections may not be usefulfor connecting to fixation members of another type. Further, theconnections of such devices may not be used for connecting to fixationmembers with a smooth outside or that do not have affirmative connectionpoints such as indentations, grooves, threads or the like.

SUMMARY OF THE INVENTION

In one embodiment, an apparatus is provided for connecting to anorthopedic implant, comprising a base having a relatively forward endand a relatively rearward end, a shaft connected to the base andslidable with respect to the base, a plate with an aperture that ispivotably connected to the shaft, and a sleeve at least partiallysurrounding the shaft and being slidable along the rod and with respectto the base. The shaft has a first position that corresponds to alocking position of the plate, and a second position that corresponds toan accepting position of the plate. Other embodiments of the apparatuscan include a ratchet operative to move the sleeve, which can beoperated by an actuator pivotably connected to a base. A stock can beattached to or integral with the base, and one or more springs can beplaced between the stock and the actuator. A catch can be connected tothe base, so that the catch has a first position that connects to theratchet and inhibits movement of the sleeve in a rearward direction, anda second position disengaged from the ratchet so that the sleeve can bemoved in a rearward direction.

Other aspects of this and other embodiments of apparatus and methodswill be apparent from the following disclosure and the knowledge ofordinary skill in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of one embodiment of a rod reducer incorporatingaspects of the present invention.

FIG. 2 is a perspective exploded view of the embodiment shown in FIG. 1.

FIG. 3 is a sectional view from the side of the embodiment shown in FIG.1.

FIG. 4 is a perspective view of the embodiment shown in FIG. 1 in anextended state.

FIG. 5 is a perspective view of the embodiment shown in FIG. 1 in anopen state.

FIG. 6 is a sectional view from the side of a forward part of theembodiment shown in FIG. 1 with a fixation element in a relativelygripped state.

FIG. 7 is a sectional view from the side of a rearward part of theembodiment shown in FIG. 1.

FIG. 8 is a perspective view of a lower portion of the embodiment shownin FIG. 1.

FIG. 9 is a perspective view of an embodiment of a portion of a shaftelement and connected structure, in a relatively gripping state, used inthe embodiment shown in FIG. 1.

FIG. 10 is a perspective view of the embodiment shown in FIG. 9 in arelatively open or inserting state.

FIG. 11 is a front view of an embodiment of a plate member used in theembodiment shown in FIG. 1.

FIG. 12 is a sectional view, taken along the lines 12-12 in FIG. 11, ofthe embodiment of the plate member shown in FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated device, and such further applicationsof the principles of the invention as illustrated therein, beingcontemplated as would normally occur to one skilled in the art to whichthe invention relates are also included.

Referring now generally to FIGS. 1-12, there is shown one embodiment ofa rod reducer 20. In that embodiment, rod reducer 20 includes a base 22(including an upper base portion 24 and a lower base portion 26 in theillustrated embodiment), a shaft element 28, a plate element 30, and asleeve element 32. Shaft element 28 is slidable with respect to base 22.Plate element 30 is pivotably connected to shaft 28 at or near an end ofshaft 28. Sleeve 32 is slidably coupled to base 22 independently ofshaft 28.

Base 22 in the illustrated embodiment includes upper base portion 24 andlower base portion 26. Upper base portion 24 is roughly rectangular,having a relatively rearward part 34 and a relatively forward part 36.Upper base portion 24 is pivotally connected to lower base portion 26,as by a flange 38 with a hole 40 that extends into lower base portion 26and is connected thereto by a pin 42 extending through hole 40 and ahole 44 in lower base portion 26. In that embodiment, the base portions24 and 26 are relatively pivotable about pin 42.

Upper portion 24 and/or lower portion 26 of base 22 may be hollowthrough much or all of their respective extents. In one embodiment ofupper base portion 24, an upper surface 46 includes an opening 47through which shaft element 28 can be contacted by a button or lever,such as lever 48, as will be described further below. Lever 48 ispivotally connected to upper base portion 24 at an end portion 49, sothat pressing on a part of pad 50 will pivot lever 48 about end portion49. Upper portion 24 also includes in the illustrated embodiment a slot51 in a side surface, and may include a second slot similar or identicalto slot 51 in the opposite side surface. Upper portion 24 may include anend portion 52 having a cavity 53 formed therein. Cavity 53 may begenerally cylindrical or rectangular, and may have an extension portion53 a at a proximal end. In an embodiment in which rod reducer 20includes a closure (described below), upper base portion 24 can includea notch 54. Notch 54 may have a surface 55 that is slanted, i.e.substantially non-parallel to the remainder of upper base portion 24, toenhance the connection and lock of the closure.

A toothed bar 56 sits substantially within upper base portion 24, and isable to slide within base 22 (one or both of base portions 24 and 26)between a forward and rearward position. Bar 56 is attached throughslot(s) 51 in upper base portion 24 to sleeve 32, so that movement ofbar 56 causes substantially identical movement of sleeve 32. In theillustrated embodiment, a connecting pin 57 connects bar 56 to sleeve 32through slot 51. It will be seen that in place of a pin, a rivet, aweld, or other structure for connecting bar 56 and sleeve 32 can beused.

Lower base portion 26 includes a ratchet mechanism for moving sleeve 32with respect to base 22, shaft 28 and plate 30. The mechanism includes adrive pawl 58 having a tooth 60 configured to engage toothed bar 56 anda slot 62, which sits substantially within lower base portion 26. Slot62, in one embodiment, has a slanted portion 62 a, and accommodates apin or boss 63 connected to lower base portion 26. The mechanism mayalso include a spring 64 (shown with cap 65) to bias pawl 58. Pawl 58 ispivotably connected at a point adjacent one end to an actuator arm 66.Actuator arm 66 is in turn pivotably connected at a point adjacent oneend to lower base portion 26. In this embodiment, lower base portion 26may also be provided with a stock or stationary arm 68, which isintegral with or attached to lower base portion 26. One or more springsmay also be provided to bias actuator arm 66 away from base portion 26or stock 68. In the illustrated embodiment, two leaf springs 70 and 72are provided. Spring 70 is attached to actuator arm 66, spring 72 isattached to stock 68, and springs 70 and 72 are connected to each other.It will be understood that a single leaf spring, for example spring 70,may be provided to bias arms 66 and 68 apart. Other structures, such asone or more coil springs or other springs, can be used in addition to orinstead of leaf springs 70 and/or 72 to provide such bias.

Squeezing actuator arm 66 toward stock 68 causes pawl 58 to moverelatively forward, and in doing so spring 64 pushes pawl upward untiltooth 60 engages bar 56. Pawl 58 thus moves bar 56 relatively forward.When actuator arm 66 is released and is biased back to a position spreadfrom stock 68, pawl 58 moves relatively backward, and when slantedportion 62 a of slot 62 contacts pin 63, pawl 58 is forced downward andcompresses spring 64.

At least one pawl for preventing or inhibiting retrograde movement ofbar 56 (and sleeve 32) is also provided in the illustrated embodiment.Although only a single pawl can be used with rod reducer 20, in theillustrated embodiment a three-pawl mechanism is provided. Pawl 74 hasone tooth 74 a, and a slot 74 b. Pawl 76 has two teeth 76 a, a pin 76 bthat extends at least partially through slot 74 b, and a slot (notshown) similar to slot 74 b. Pawl 78 has three teeth 78 a in thisembodiment and may have a pin 78 b that cooperates with the slot of pawl76. In this embodiment, pawls 74, 76, 78 are nested, e.g. pawls 74 and76 are substantially hollow, and pawl 78 fits at least partially withinthe hollow of pawl 76, and pawls 76 and 78 fit at least partially withinpawl 74. Pawl 74 may be connected to or integral with a release lever80, which is pivotally connected to lower base portion 26 as at point82. Pulling release lever 80 pivots pawl 74. Pawl 74 may move withrespect to pawls 76 and/or 78, at least until an end of slot 74 bcontacts pin 76 b, at which time further pulling of lever 80 pivots pawl76 as well. A similar relationship can exist between pawl 76 (and itsslot) and pawl 78 and its pin 78 b. The teeth of adjacent pawls (e.g.pawls 74 and 76, or pawls 76 and 78) may be spaced apart a specificamount that is smaller than and/or not an integer-multiple of thedistance between the teeth (crest to crest or trough to trough) of thetoothed bar 56, so that incremental advancements of bar 56 (and sleeveelement 32) can be made that are smaller than the distance between theteeth of bar 56. For example, reducer 20 may include a bar 56 having aspace of two millimeters (2 mm) between teeth. A pawl having multipleteeth (i.e. pawls 76 and 78 in the illustrated embodiment) will alsohave two millimeters between the teeth to mate properly with bar 56.However, the distance between the pawls may be set at 0.7 millimeters,in a specific embodiment. Thus, starting from a position in which onepawl is engaged with bar 56 (i.e. crest(s) on the pawl in associatedtrough(s) of bar 56), a 0.7 millimeter advancement of bar 56 will resultin the teeth of another pawl engaging bar 56.

A leaf spring 84 is provided in this embodiment, connected to theunderside of lower base portion 26. Spring 84 can include threesubstantially parallel fingers 86, 88, 90, each of which tends to biasone of the pawls 74, 76, 78. Thus, finger 86 of spring 84 biases pawl 74upward and into contact with bar 56, finger 88 similarly biases pawl 76upward, and finger 90 similarly biases pawl 78 upward.

The illustrated embodiments of upper base portion 24 and lower baseportion 26 also include a closure that locks together base portions 24and 26 during use, and can be opened to allow upper base portion to bepivoted away from lower base portion 26. Opening reducer 20 in thisfashion allows cleaning, sterilization, maintenance or other operationsto be performed on the apparatus within base 22, including theabove-described ratchet mechanism, pawls, release lever, toothed bar, orother features. In one embodiment, a latch 92 having an end plate 94 anda top flange 96 is pivotably connected to a substantially C-shapedconnector 98, which in turn is pivotably connected to lower base portion26. Flange 96 may be complementary with notch 54 of upper base portion24. For example, the length of flange 96 may be substantially the sameas the length of notch 54, and flange 96 may have an underside 96 a thathas the same angle as slanted surface 55. Latch 92 may be released bylifting its lower end so that connector 98 pivots with respect to lowerbase portion 26 and latch 92 and lifts flange 96 away from notch 54, andby pivoting latch 92 away from upper base portion 24. Latch 92 may beengaged in substantially the reverse manner, by positioning flange 96adjacent to notch 54 then pressing down on latch 92 until latch 92 andconnector 98 pivot and snap into place, with end plate 94 abutting upperend portion 24 and lower end portion 26.

Shaft element 28 may be elongated and roughly rectangular. In theillustrated embodiment, shaft 28 extends adjacent top surface 46 ofupper base portion 24, to a point adjacent to or at the end ofrelatively forward part 34 of base 22. In one embodiment a relativelyrearward portion or end of shaft 28 is attached to a lever 48 throughopening 47 in relatively rearward part 34 of upper base portion 24. Aspreviously described, lever 48 can be pivoted by the user so as to moveshaft 28 along upper base portion 24.

In a specific embodiment, shaft 28 has an elongated portion 100 and aplunger 102 connected to a relatively forward part of elongated portion100. Elongated portion 100 is connected to lever 48 at or near one end,and includes a tab or tongue 104 that connects to plunger 102 and anindentation 106 for connecting with plate member 30, as will bedescribed further below. Plunger 102 includes a groove 108 thataccommodates tongue 104 and a rear portion 110 having an end surface 112and a ledge 114. Alternatively, plunger 102 and elongated portion 100could be integral or otherwise connected or attached.

The illustrated embodiment includes an inner coil spring 116 and anouter coil spring 118 for biasing shaft 28 forward. Spring 116 abuts endsurface 112, and spring 118 abuts ledge portion 114 of plunger 102. Bothsprings abut an end surface of cavity 53 in upper base portion 24, andif extension portion 53 a of cavity 53 is present, inner spring 116 mayextend within extension portion 53 a. Springs 116 and 118 may beconcentric. Other types of biasing devices could be used in place of oneor both coil springs 116 and 118, or only one spring could be used, tobias plunger 102 and shaft 28 forward. When lever 48 is depressed, itpivots to move shaft 28 relatively backward, and springs 116 and 118 arecompressed between plunger 102 and a surface of cavity 53. When lever 48is released, springs 116 and 118 force plunger 102 and shaft 28 forward.A block element 119 or other barrier may be provided to limit theforward range of motion of plunger 102

Plate element 30, in the illustrated embodiment, is a substantiallyrectangular piece with an aperture 120 and an upper notch or gap 122.Aperture 120 can go all the way through plate 30, or may end withinplate 30. Gap 122 is sized to accommodate a portion of shaft 28. As oneexample, notch 122 can accommodate a part of elongated portion 100 ofshaft 28. Plate element 30 has an upper edge 124, a rounded surface 126adjacent upper edge 124 and gap 122, and a lower rounded edge 128.Rounded surfaces 126 and 128 facilitate pivoting of plate 30. In oneembodiment, indentation 106 of shaft element 28 may fit with roundedsurface 126, so that indentation 106 and rounded surface 126 are able torotate with respect to each other. Thus, linear movement of shaft 28causes indentation 106 to move linearly and push plate element 30, sothat indentation 106 and rounded surface 126 move with respect to eachother and plate 30 pivots substantially around rounded edge 128.Alternatively, plate element 30 could be connected to shaft element 28in or adjacent to gap 122 by placing a pin or axle through shaft 28 andconnecting to plate 30 on either side of gap 122, so that plate 30 canpivot with respect to shaft 28. As another example, plate 30 couldinclude extensions in or adjacent to gap 122 that may be inserted intoshaft 28 and act as an axle for plate 30.

In one specific embodiment, aperture 120 of plate element 30 ispartially tapered. For example, aperture 120 can include aconstant-diameter portion 130 and a varying-diameter portion 132.Alternatively, aperture 120 may have a constant diameter throughout, maybe uniformly tapered throughout, or may have other surfaceconfigurations. The minimum diameter of aperture 120 is at leastsomewhat larger than the external diameter or other dimension of a bonefixation member with which reducer 20 is to be used. Further, in aspecific embodiment tapered portion 132 is oriented so that the largestdiameter of tapered portion 132 is on the distal surface of plate 30,i.e. that surface furthest from lever 48, to make insertion of a part ofa bone fixation member into aperture 120 (as described below) easier.Plate element 30 and its aperture 120 form a locking mechanism forholding a fixation member within rod reducer 20. The surfaces of plateelement 30, including those bounding aperture 120, could be roughened aswith knurling, one or more grooves or ridges, or with other surfaceirregularities or roughening methods in addition to or in place of atapered configuration. Such roughening can create or improve contact,grip or purchase between plate 30 and a fixation member during use ofrod reducer 20.

Sleeve element 32 is a generally hollow rectangular member in theillustrated embodiment, though other configurations could also be used.Sleeve 32, as noted above, is slidably connected to base 22,particularly upper base member 24, between a relatively rearwardposition and a relatively forward position. One example of a relativelyrearward position of sleeve element 32 is shown in FIGS. 1 and 3, wheresleeve 32 covers a substantial portion of upper base portion 24, and oneend of sleeve 32 is adjacent lever 48 while the other end of sleeve 32is adjacent a distal end of shaft element 28 and plate element 30. Anexample of a relatively forward position is shown in FIG. 4, wheresleeve 32 covers a lesser portion of upper base portion 24, and a distalend of sleeve 32 extends substantially beyond the distal end of shaftelement 28. In a specific embodiment, sleeve 32 can have a range ofsliding movement of about fifty millimeters, i.e., the distal end ofsleeve 32 is about fifty millimeters further from base 22 when sleeve 32is in a relatively forward-most position than when sleeve 32 is in arelatively rearward-most position. Sleeve 32 is also slidable relativeto shaft element 28 and plate element 30. Sleeve element 32 may have adistal portion or end that is substantially flat, or may be otherwiseconfigured, and may be intended for contact with implants such as aspinal rod, an orthopedic connector, and/or an orthopedic plate

The use of rod reducer 20 will now be described in the context of usewith a substantially cylindrical bone screw 140 (FIG. 6, 9-10), such asa Schanz-type screw, and a rod for spinal correction. The illustratedembodiment of screw 140 has a substantially cylindrical upper part 142and a threaded lower part 144. The upper part 142 may have an externalor internal print to enable screw 140 to be threaded into a bone orotherwise manipulated. Screw 140 may have a print 146, which may behexagonal and internal as shown or may be of other configuration (e.g.hexalobed or slotted internal print, or an external hexagonal or squareprint). The threads of threaded part 144 are intended to be securelyfastened into a bone, and may be cancellous threads or another varietyof threads useful in orthopedic surgery. Such screws may be used in oramong one or more parts of the spine, including cervical, thoracic,lumbar and/or sacral portions. Although the use of rod reducer 20 willbe described in the above context, rod reducer 20 could be used with avariety of screws, hooks or other fixation implants, with an elongatedimplant member other than a rod, or in connection with orthopedicimplants in other parts of the body than the spine.

As with other types of orthopedic surgery, an incision is made andaccess is gained to the surgical site. The approach to the surgical sitecan be an open approach, i.e. a relatively long incision with retractionof underlying tissue, or can be a minimally-invasive approach, i.e. arelatively short incision with implants and tools inserted through tubesor other devices to the surgical site. The embodiments disclosed hereincan be used in either approach, or with other surgical techniques. It isnoted that a relatively narrow distal end of rod reducer 20 will beadvantageous in minimally-invasive surgery.

After access to the surgical site has been obtained, screws such asscrew 140 are inserted into bone tissue. Such screws may be pre-fittedwith connectors (not shown), which commonly have an aperture forreceiving a part of a screw 140 and a channel for accommodating part ofan elongated support member. Such connectors may be placed on or oversuch screws after insertion of screws 140 into bone. An elongatedmember, such as a spinal or other orthopedic rod, is inserted into thesurgical site, and placed adjacent one or more of screws 140. If notalready present, connectors may be loosely placed on the rod prior toinsertion of the rod to the surgical site. In that case, the rod isinserted, and the connectors can be moved with respect to the rod untileach is on or over a screw 140. The screws, connectors and rod aremanipulated so that a part of the rod is in or near the channel of eachconnector, and each screw 140 extends through the aperture of aconnector so that a portion of the screw 140 sticks out of theconnector.

Rod reducer 20 is inserted to the surgical site. The surgeon or otheroperator moves shaft 28 backward to a relatively backward position, inone embodiment by pressing lever 48. Pressing lever 48 moves shaftelement 28 backward, as described above, and causes plate element 30 topivot. In a specific embodiment, plate 30 pivots to a positionsubstantially perpendicular to sleeve element 32, and/or to a positionsuch that aperture 120 of plate 30 is substantially perpendicular tosleeve 32. A portion of the upper part 142 of screw 140 is inserted intoaperture 120.

Once a portion of screw 140 is within aperture 120, the surgeon movesshaft element 28 forward to a relatively forward position. In oneembodiment, the surgeon may simply release lever 48, allowing springs116, 118 to bias shaft 28 to a forward position. When shaft 28 moves toa relatively forward position, plate 30 pivots so that the surfacebounding tapered portion 132 of aperture 120 (and/or the surfacebounding constant-diameter portion 130) contacts a part of screw 140. Inembodiments in which such surface is knurled or otherwise roughened,and/or springs 116, 118 is relatively strong, parts of plate 30 may biteinto or otherwise deform a part of screw 140, or part(s) of plate 30 maybe deformed. With shaft 28 in a relatively forward position, screw 140is held by plate 30.

With screw 140 so gripped, the surgeon abuts the distal end of sleeve 32against the rod or other implant, device or tissue. The surgeon squeezesactuator arm 66 toward stock 68, causing toothed bar 56 and sleeve 32 tomove distally or away from lever 48 on upper base portion 24, asdiscussed above. Sleeve 32 slides around upper base portion 24, plate 30and screw 140. Consequently, when actuator arm 66 is squeezed, sleeve 32is forced against the implant or other structure it abuts. Such implantor structure moves with respect to screw 140 and the tissue to which itis connected, such that screw 110 moves closer to or past such implantor other structure. For example, where a spinal rod is being reducedinto a connector piece connected to screw 140, sleeve 32 abuts the rod.When actuator arm 66 is squeezed, sleeve 32 pushes the rod toward orpast screw 140, and the rod can be pushed or otherwise maneuvered inthis way into an opening in the connector piece connected to screw 140.Similarly, if a connector or other implant part must be pushed furtheronto a fixation member such as screw 140, sleeve 32 is placed so that itabuts such implant and screw 140 is connected to plate 30, then actuatorarm 66 is squeezed one or more times until the desired relative positionof fixation member and implant is achieved.

Bar 56 and sleeve 32 are retained in position by one or more of pawls74, 76, 78 when actuator arm 66 is released by the surgeon betweensqueezes or after the desired amount of movement of sleeve 32 isachieved. Actuator arm 66 is squeezed one or more times until sleeve 32pushes the implant or other structure it abuts a desired distance withrespect to screw 140. When that desired distance is reached, for examplewhen a spinal rod is reduced so that it sits at least partially withinanother implant part, then the surgeon can secure the rod to the otherimplant part or take other fixation or surgical action.

When reduction is no longer needed, the surgeon can press lever 48,causing shaft 28 to move rearward and pivot plate 30. In a specificembodiment, plate 30 pivots to a position substantially perpendicular tosleeve element 32, and/or to a position such that aperture 120 of plate30 is substantially perpendicular to sleeve 32. Screw 140 can bedisengaged and withdrawn from plate 30. Catch 96 can be pulled to resetbar 56 and sleeve 32 to a relatively rearward position, and allowreducer 20 to be used with respect to other screws or implants in thegiven patient. Reducer 20 can be made for use with a single patient, oras noted above may be made to be cleaned and sterilized for later usewith other patients, as for example by releasing latch 92 and pivotingupper base portion 24 with respect to lower base portion 26 for accessto internal parts of reducer 20.

It will be seen that several changes may be made to the above structure.For example, shaft 24 may be made of a single piece, rather than severalinterconnected pieces. Spring 68 is preferably a coiled compressionspring, but an extension spring or other types of springs may be used inaddition to or in place of spring 68. Reducer 20, or parts of it, arepreferably made of biocompatible materials such as stainless steel orcertain sturdy plastics. The materials for making reducer 20 may also bechosen to allow resterilization and reuse of reducer 20.

Other embodiments of rod reducer 20 or parts of it are also possible.For example, a rod reducer 20 in which upper base portion 24 and lowerbase portion 26 are fixed together or integral with each other so thatthose portions are not separable or pivotable with respect to eachother. Base 22 may be effectively a single piece, housing or connectedto the structures described above.

In place of lever 48, a button or slider could be connected to shaft 28to enable the user to pull back on shaft 28. Such a slider may besubstantially triangular, concave, or otherwise configured, and may besituated atop upper surface 46. Pulling back on the slider retractsshaft 28 to rotate plate 30 and allow a fixation member to be insertedthrough plate 30. Releasing the slider allows shaft 28 to be biasedforward to rotate plate 30 to lock onto or hold the fixation member.

In other embodiments, a single spring may be used to bias plunger 102relatively forward. Plunger 102 and the forward part of base 22 could beconfigured to use an extension spring for such bias. In that case,pulling back on shaft 28 would extend such a spring, and releasing shaft28 would allow such a spring to pull plunger 102 and the rest of shaft28 forward. If desired, plunger 102 can be made of two or more connectedparts. Further, plate member 30 may be of a somewhat differentconfiguration. For example, plate 30 could be substantially square or ofother shape.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionare desired to be protected.

1. An apparatus for connecting to an orthopedic implant, comprising: abase having a relatively forward end and a relatively rearward end; ashaft connected to said base, said shaft being slidable with respect tosaid base between first and second positions; a plate having anaperture, said plate being pivotably connected to said shaft, such thatwhen said shaft is in said first position said plate is in a positionfor locking to an implant, and when said shaft is slid to said secondposition, said plate pivots to a position for accepting insertion of apart of an implant; a sleeve at least partially surrounding said shaftand being slidable along said shaft and slidable with respect to saidbase and said plate; a ratchet mechanism connected to said base and saidsleeve, said ratchet mechanism operable to move said sleeve with respectto said base, said shaft and said plate; and a handle including anactuator movably connected to said base, said actuator operating saidratchet mechanism when said actuator is moved relative to said base. 2.The apparatus of claim 1, wherein said actuator is pivotably connectedto said base, said actuator operating said ratchet mechanism when saidactuator is pivoted relative to said base.
 3. The apparatus of claim 2,wherein said handle further includes a stock rigidly connected to saidbase.
 4. The apparatus of claim 3, further comprising at least onespring between said actuator and said stock, said at least one springtending to bias the actuator and stock apart.
 5. The apparatus of claim4, wherein said at least one spring comprises a leaf spring.
 6. Theapparatus of claim 4, wherein said at least one spring comprises a firstleaf spring connected to said actuator and a second leaf springconnected to said stock, wherein said leaf springs are connectedtogether so as to bias the actuator and stock apart.
 7. The apparatus ofclaim 4, further comprising a stop connected to said base, said stophaving a first position connected to said ratchet mechanism so thatmovement in a rearward direction of said sleeve is limited, and a secondposition disengaged from said ratchet mechanism so that said sleeve canbe moved in a rearward direction.
 8. The apparatus of claim 7, whereinsaid stop is biased toward said first position.
 9. An apparatus forconnecting to an orthopedic implant, comprising: a base having arelatively forward end and a relatively rearward end; a shaft connectedto said base, said shaft being slidable with respect to said basebetween first and second positions; a plate having an aperture, saidplate being pivotably connected to said shaft, such that when said shaftis in said first position said plate is in a position for locking to animplant, and when said shaft is slid to said second position, said platepivots to a position for accepting insertion of a part of an implant; asleeve at least partially surrounding said shaft and being slidablealong said shaft and slidable with respect to said base and said plate;a ratchet mechanism connected to said base and said sleeve, said ratchetmechanism operable to move said sleeve with respect to said base, saidshaft and said plate; and a stop connected to said base, said stophaving at least one position connected to said ratchet mechanism inwhich movement in a rearward direction of said sleeve is limited, and aposition disengaged from said ratchet mechanism so that said sleeve canbe moved in a rearward direction.
 10. The apparatus of claim 9, whereinsaid stop comprises at least one pawl that is pivotable between said atleast one position connected to said ratchet mechanism and said positiondisengaged from said ratchet mechanism.
 11. The apparatus of claim 10wherein said stop comprises three pawls capable of operatingindependently of each other.
 12. The apparatus of claim 11 wherein saidpawls are nested.
 13. An apparatus for connecting to an orthopedicimplant, comprising: a base having a relatively forward end and arelatively rearward end; a shaft connected to said base, said shaftbeing slidable with respect to said base between first and secondpositions; a plate having an aperture, said plate being pivotablyconnected to said shaft, such that when said shaft is in said firstposition said plate is in a position for locking to an implant, and whensaid shaft is slid to said second position, said plate pivots to aposition for accepting insertion of a part of an implant; and a sleeveat least partially surrounding said shaft and being slidable along saidshaft and slidable with respect to said base and said plate, whereinsaid aperture of said plate is at least partially tapered.
 14. Theapparatus of claim 13, wherein said aperture of said plate has aconstant diameter section.
 15. The apparatus of claim 13, wherein saidplate includes a roughened surface adjacent said aperture.
 16. Theapparatus of claim 13, wherein said aperture of said plate is uniformlytapered.
 17. An apparatus for connecting to an orthopedic implant,comprising: a base having a relatively forward end and a relativelyrearward end; a shaft connected to said base, said shaft being slidablewith respect to said base between first and second positions; a platehaving an aperture, said plate being pivotably connected to said shaft,such that when said shaft is in said first position said plate is in aposition for locking to an implant, and when said shaft is slid to saidsecond position, said plate pivots to a position for accepting insertionof a part of an implant; a sleeve at least partially surrounding saidshaft and being slidable along said shaft and slidable with respect tosaid base and said plate; and wherein said plate includes a roundedsurface and said shaft includes an indentation, and said indentation andsaid rounded surface are adjacent each other.
 18. An apparatus forconnecting to an orthopedic implant, comprising: a base having arelatively forward end and a relatively rearward end; a shaft connectedto said base, said shaft being slidable with respect to said basebetween first and second positions; a plate having an aperture, saidplate being pivotably connected to said shaft, such that when said shaftis in said first position said plate is in a position for locking to animplant, and when said shaft is slid to said second position, said platepivots to a position for accepting insertion of a part of an implant; asleeve at least partially surrounding said shaft and being slidablealong said shaft and slidable with respect to said base and said plate;and wherein said plate includes a rounded surface that facilitatespivoting of said plate.
 19. An apparatus for connecting to an orthopedicimplant, comprising: a base having a relatively forward end and arelatively rearward end; a shaft connected to said base, said shaftbeing slidable with respect to said base between first and secondpositions; a plate having an aperture, said plate being pivotablyconnected to said shaft, such that when said shaft is in said firstposition said plate is in a position for locking to an implant, and whensaid shaft is slid to said second position, said plate pivots to aposition for accepting insertion of a part of an implant; a sleeve atleast partially surrounding said shaft and being slidable along saidshaft and slidable with respect to said base and said plate; and whereinsaid sleeve includes an end portion adapted to contact at least one ofthe group consisting of a spinal rod, an orthopedic connector, and anorthopedic plate.
 20. An apparatus for connecting to an orthopedicimplant, comprising: a base having a relatively forward end and arelatively rearward end; a shaft connected to said base, said shaftbeing slidable with respect to said base between first and secondpositions; a plate having an aperture, said plate being pivotablyconnected to said shaft, such that when said shaft is in said firstposition said plate is in a position for locking to an implant, and whensaid shaft is slid to said second position, said plate pivots to aposition for accepting insertion of a part of an implant; a sleeve atleast partially surrounding said shaft and being slidable along saidshaft and slidable with respect to said base and said plate; and whereinsaid shaft includes an elongated portion and a plunger portion connectedto each other.
 21. The apparatus of claim 20, wherein said elongatedportion includes a tongue and said plunger portion includes a groove,and said tongue is at least partially within said groove.
 22. Theapparatus of claim 20, further comprising at least one spring abuttingsaid plunger to bias said plunger toward said relatively forward end ofsaid base.
 23. The apparatus of claim 20, further comprising at leasttwo springs abutting said plunger to bias said plunger toward saidrelatively forward end of said base.
 24. The apparatus of claim 23,wherein said springs are substantially concentric.
 25. An apparatus forconnecting to an orthopedic implant, comprising: a base having arelatively forward end and a relatively rearward end; a shaft connectedto said base, said shaft being slidable with respect to said basebetween first and second positions; a plate having an aperture, saidplate being pivotably connected to said shaft, such that when said shaftis in said first position said plate is in a position for locking to animplant, and when said shaft is slid to said second position, said platepivots to a position for accepting insertion of a part of an implant; asleeve at least partially surrounding said shaft and being slidablealong said shaft and slidable with respect to said base and said plate;and wherein said base comprises an upper base portion and a lower baseportion connected together.
 26. The apparatus of claim 25, furthercomprising a closure connected to said upper base portion and said lowerbase portion, wherein closing said closure holds said base portionstogether, and opening said closure allows separation of at least a partof said upper base portion from at least a part of said lower baseportion.
 27. The apparatus of claim 26, wherein said closure includes alatch.
 28. The apparatus of claim 26, wherein said base portions arepivotably connected, whereby opening said closure allows said baseportions to pivot with respect to each other.
 29. The apparatus of claim25, wherein said base portions are pivotably connected together.
 30. Anapparatus for use in orthopedic surgery, comprising: an orthopedicimplant; a plate member having first and second edges substantiallyopposite each other and an aperture extending entirely through saidplate member; a shaft connected to said plate member adjacent said firstedge of said plate member, said shaft being movable to pivot said platemember substantially around said second edge of said plate; a sleeveslidable with respect to said shaft; and a base connected to said shaft,wherein said aperture is sized to allow insertion of at least part ofthe orthopedic implant, and wherein said plate member has a firstposition in which said aperture is relatively open and such insertioncan be accomplished with the orthopedic implant positioned within saidaperture and extending through said plate member, and a second positionin which said aperture is relatively closed and an inner surface of saidaperture in said plate is in contact with the orthopedic implant. 31.The apparatus of claim 30, further comprising a stock connected to saidbase.
 32. The apparatus of claim 30, wherein said base comprises anupper base portion and a lower base portion connected together.
 33. Theapparatus of claim 30, wherein said plate includes a roughened surfaceadjacent said aperture.
 34. The apparatus of claim 30, wherein saidsecond edge of said plate includes a rounded surface that facilitatespivoting of said plate.
 35. The apparatus of claim 30, wherein saidsleeve includes an end portion adapted to contact at least one of thegroup consisting of a spinal rod, an orthopedic connector, and anorthopedic plate.
 36. An apparatus for use in orthopedic surgery,comprising: a plate member having first and second edges substantiallyopposite each other and an aperture; a shaft connected to said platemember adjacent said first edge of said plate member, said shaft beingmovable to pivot said plate member substantially around said second edgeof said plate; a sleeve slidable with respect to said shaft; a baseconnected to said shaft; an actuator movably connected to said base,said actuator operating said ratchet mechanism when said actuator ismoved relative to said base; and wherein said aperture is sized to allowinsertion of at least part of an orthopedic implant, and wherein saidplate member has a first position in which said aperture is relativelyopen and such insertion can be accomplished, and a second position inwhich said aperture is relatively closed and said plate can contact theorthopedic implant.
 37. An apparatus for use in orthopedic surgery,comprising: a plate member having first and second edges substantiallyopposite each other and an aperture; a shaft connected to said platemember adjacent said first edge of said plate member, said shaft beingmovable to pivot said plate member substantially around said second edgeof said plate; a sleeve slidable with respect to said shaft; a baseconnected to said shaft; a stock connected to said base; a first leafspring connected to said actuator and a second leaf spring connected tosaid stock, wherein said leaf springs are connected together so as tobias the actuator and stock apart; and wherein said aperture is sized toallow insertion of at least part of an orthopedic implant, and whereinsaid plate member has a first position in which said aperture isrelatively open and such insertion can be accomplished, and a secondposition in which said aperture is relatively closed and said plate cancontact the orthopedic implant.
 38. An apparatus for use in orthopedicsurgery, comprising: a plate member having first and second edgessubstantially opposite each other and an aperture; a shaft connected tosaid plate member adjacent said first edge of said plate member, saidshaft being movable to pivot said plate member substantially around saidsecond edge of said plate; a sleeve slidable with respect to said shaft;a base connected to said shaft, wherein said base comprises an upperbase portion and a lower base portion connected together and whereinsaid base portions are pivotably connected together; and wherein saidaperture is sized to allow insertion of at least part of an orthopedicimplant, and wherein said plate member has a first position in whichsaid aperture is relatively open and such insertion can be accomplished,and a second position in which said aperture is relatively closed andsaid plate can contact the orthopedic implant.
 39. The apparatus ofclaim 38, further comprising a closure connected to said upper baseportion and said lower base portion, wherein closing said closure holdssaid base portions together, and opening said closure allows separationof at least a part of said upper base portion from at least a part ofsaid lower base portion.
 40. The apparatus of claim 39, wherein openingsaid closure allows said base portions to pivot with respect to eachother.
 41. The apparatus of claim 39, wherein said closure includes alatch.
 42. An apparatus for use in orthopedic surgery, comprising: aplate member having first and second edges substantially opposite eachother and an aperture extending entirely through said plate member, saidaperture including an inner circular surface; and a shaft connected tosaid plate member adjacent said first edge of said plate member, saidshaft being movable to pivot said plate member substantially around saidsecond edge of said plate, wherein said aperture is sized to allowinsertion of at least part of an orthopedic implant, and wherein saidplate member has a first position in which said aperture is relativelyopen and such insertion can be accomplished, and a second position inwhich said aperture is relatively closed and said plate can contact theorthopedic implant, and wherein said inner circular surface of saidaperture of said plate is at least partially tapered.
 43. An apparatusfor use in orthopedic surgery, comprising: a plate member having firstand second edges substantially opposite each other and an aperture; anda shaft connected to said plate member adjacent said first edge of saidplate member, said shaft being movable to pivot said plate membersubstantially around said second edge of said plate, wherein saidaperture is sized to allow insertion of at least part of an orthopedicimplant, and wherein said plate member has a first position in whichsaid aperture is relatively open and such insertion can be accomplished,and a second position in which said aperture is relatively closed andsaid plate can contact the orthopedic implant, and wherein said apertureof said plate is at least partially tapered, and wherein said apertureof said plate has a constant diameter section.
 44. An apparatus for usein orthopedic surgery, comprising: a plate member having first andsecond edges substantially opposite each other and an aperture; and ashaft connected to said plate member adjacent said first edge of saidplate member, said shaft being movable to pivot said elate membersubstantially around said second edge of said plate, wherein saidaperture is sized to allow insertion of at least part of an orthopedicimplant, and wherein said plate member has a first position in whichsaid aperture is relatively open and such insertion can be accomplished,and a second position in which said aperture is relatively closed andsaid plate can contact the orthopedic implant, and wherein said apertureof said plate is at least partially tapered, and wherein said apertureof said plate is uniformly tapered.
 45. An apparatus for use inorthopedic surgery, comprising: a plate member having first and secondedges substantially opposite each other and an aperture; and a shaftconnected to said plate member adjacent said first edge of said platemember, said shaft being movable to pivot said plate membersubstantially around said second edge of said plate, wherein saidaperture is sized to allow insertion of at least part of an orthopedicimplant, and wherein said plate member has a first position in whichsaid aperture is relatively open and such insertion can be accomplished,and a second position in which said aperture is relatively closed andsaid plate can contact the orthopedic implant, and wherein said plateincludes a rounded surface and said shaft includes an indentation, andsaid indentation and said rounded surface are adjacent each other. 46.An apparatus for use in orthopedic surgery, comprising: a plate memberhaving first and second edges substantially opposite each other and anaperture; and a shaft connected to said plate member adjacent said firstedge of said plate member, said shaft being movable to pivot said platemember substantially around said second edge of said plate, wherein saidaperture is sized to allow insertion of at least part of an orthopedicimplant, and wherein said plate member has a first position in whichsaid aperture is relatively open and such insertion can be accomplished,and a second position in which said aperture is relatively closed andsaid plate can contact the orthopedic implant, and wherein said shaftincludes an elongated portion and a plunger portion connected to eachother.
 47. The apparatus of claim 46, wherein said elongated portionincludes a tongue and said plunger portion includes a groove, and saidtongue is at least partially within said groove.
 48. The apparatus ofclaim 46, further comprising at least one spring abutting said plungerto bias said plunger toward said relatively forward end of said base.49. The apparatus of claim 46, further comprising at least two springsabutting said plunger to bias said plunger toward said relativelyforward end of said base.
 50. The apparatus of claim 49, wherein saidsprings are substantially concentric.
 51. An apparatus for use inorthopedic surgery, comprising: a plate member having first and secondedges substantially opposite each other and an aperture; a shaftconnected to said plate member adjacent said first edge of said platemember, said shaft being movable to pivot said plate membersubstantially around said second edge of said plate; and a leverconnected to said shaft, wherein operating said lever causes said shaftto move, thereby pivoting said plate, and wherein said aperture is sizedto allow insertion of at least part of an orthopedic implant, andwherein said plate member has a first position in which said aperture isrelatively open and such insertion can be accomplished, and a secondposition in which said aperture is relatively closed and said plate cancontact the orthopedic implant.
 52. An apparatus for use in orthopedicsurgery, comprising: a plate member having first and second edgessubstantially opposite each other and an aperture; a shaft connected tosaid plate member adjacent said first edge of said plate member, saidshaft being movable to pivot said plate member substantially around saidsecond edge of said plate; and a slider connected to said shaft, whereinoperating said slider causes said shaft to move, thereby pivoting saidplate, and wherein said aperture is sized to allow insertion of at leastpart of an orthopedic implant, and wherein said plate member has a firstposition in which said aperture is relatively open and such insertioncan be accomplished, and a second position in which said aperture isrelatively closed and said plate can contact the orthopedic implant. 53.An apparatus for use in orthopedic surgery, comprising: a plate memberhaving first and second edges substantially opposite each other and anaperture; a shaft connected to said plate member adjacent said firstedge of said plate member, said shaft being movable to pivot said platemember substantially around said second edge of said plate; a sleeveslidable with respect to said shaft; a ratchet mechanism operable tomove said sleeve with respect to said shaft and said plate; and a baseconnected to said shaft, wherein said aperture is sized to allowinsertion of at least part of an orthopedic implant, and wherein saidplate member has a first position in which said aperture is relativelyopen and such insertion can be accomplished, and a second position inwhich said aperture is relatively closed and said plate can contact theorthopedic implant.
 54. The apparatus of claim 53 further comprising astop connected to said base, said stop having at least one positionconnected to said ratchet mechanism in which movement in a rearwarddirection of said sleeve is limited, and a position disengaged from saidratchet mechanism so that said sleeve can be moved in a rearwarddirection.
 55. The apparatus of claim 54, wherein said stop comprises atleast one pawl that is pivotable between said at least one positionconnected to said ratchet mechanism and said position disengaged fromsaid ratchet mechanism.
 56. The apparatus of claim 55 wherein said stopcomprises two pawls capable of operating independently of each other.57. The apparatus of claim 55 wherein said stop comprises three pawlscapable of operating independently of each other.
 58. The apparatus ofclaim 57 wherein said pawls are nested.